Maintaining Granite and Marble Countertops
The installers sealed your new stone before leaving your house. Sealer protects the surface of the stone against penetration of fluid. This typically only needs to be done once a year, depending on the use of the surface and how you clean it. If it is a kitchen surface and fried foods are prepared often, then cleaning will generally be more aggressive, shortening the life of the sealant. Cleaning with alcohol-based products will also speed the deterioration of sealants. We recommend the use of petroleum-based sealers, as they tend to be tougher and more effective than those that are water-based. Maintaining your sealer is much more important on light stones than on dark ones. Dark colored stones are generally only susceptible to oil based stains, where light colored stone can be stained by oil or strong colored liquids. Every day products do not affect countertops if they are wiped off right away. It is strongly recommended to avoid leaving mustard, vinegar, oil or red wine spills over a long period of time, as they may penetrate the protective coat of the sealant and leave hard to remove marks or stains in the stone.
For clean-up you should use any detergent-based, PH balanced general purpose cleaner like 409, Fantastic, etc. Please do not use any Ammonia based products, it will shorten the life of the sealant. The use of organic oxidizers such as Oxy Clean and lye-based products such as oven cleaner can cause the stone to discolor. Additionally, the use of abrasives and concentrated acids like C.L.R. should also be avoided; they can etch the surface and dull the finish over time.
Granite and Marble are heat resistant to a point; it is okay to put hot pots and pans directly on the surface if the do not exceed the boiling temperature of water. Putting items that retain heat exceeding 212° F could cause stress fractures in the stone.
In most cases the use of knives to cut on top of your stone will not damage the surface; however it can dull or even destroy the knives edge.